In situ ATR studies on the mechanism of limonene epoxidation over PW-Amberlite
نویسندگان
چکیده
Introduction PW-Amberlite is a promising catalyst for limonene epoxidation with aqueous hydrogen peroxide and acetonitrile as solvent; limonene conversion and limonene epoxide selectivity higher than 80 % and 90 %, respectively, have been reported [1,2]. The mechanistic pathway proposed for limonene epoxidation on PW-Amberlite [3], includes the interaction of H2O2 with peroxophosphotungstate species to form polyperoxophosphotungstate active sites, where limonene is adsorbed and reaction takes place, Eqs. 1 4. The catalytic cycle is completed with reaction products desorption. In situ Attenuated Total Reflection (ATR) IR spectroscopy is used in this contribution to follow the time course reaction.
منابع مشابه
Epoxidation of Alkenes and Oxidation of Alcohols with Hydrogen Peroxide Catalyzed by a Fe (Br8TPPS) Supported on Amberlite IRA-400
Iron (III) meso-tetrakis(p-sulfonatophenyl)-β-octabromoporphyrin supported on Amberlite IRA- 400 [Fe(Br8 TPPS)-Ad-400] is a robust and efficient catalyst for oxidation of alkenes and alcohols at room temperature. The catalyst exhibits a high activity and stability in hydrocarbon oxidation by H2 O2 . The method was useful in the oxidation of various primary, secondary-aliphatic, alicyclic and ar...
متن کاملThe epoxidation of limonene over the TS-1 and Ti-SBA-15 catalysts.
Limonene belongs to a group of very important intermediates used in the production of fine chemicals. This monoterpene compound can be obtained from peels of oranges or lemon which are a (biomass) waste from the orange juice industry. Thus, limonene is a renewable, easy available and a relatively cheap compound. This work presents preliminary studies on the process of limonene epoxidation over ...
متن کاملMechanistic studies on the Mukaiyama epoxidation.
A detailed mechanistic study on the Mukaiyama epoxidation of limonene with dioxygen as oxidant, bis(acetylacetonato)nickel(II) as catalyst, and an aldehyde as co-reagent is reported. All major products of the reaction have been quantitatively identified, both with isobutyraldehyde and 2-methylundecanal as co-reacting aldehydes. Limonene epoxide is formed in good yield. The main products evolvin...
متن کاملMechanism of Bacterial Inactivation by (+)-Limonene and Its Potential Use in Food Preservation Combined Processes
This work explores the bactericidal effect of (+)-limonene, the major constituent of citrus fruits' essential oils, against E. coli. The degree of E. coli BJ4 inactivation achieved by (+)-limonene was influenced by the pH of the treatment medium, being more bactericidal at pH 4.0 than at pH 7.0. Deletion of rpoS and exposure to a sub-lethal heat or an acid shock did not modify E. coli BJ4 resis...
متن کاملChemical routes for the transformation of biomass into chemicals.
3.2.3. Hydroformylation 2467 3.2.4. Dimerization 2468 3.2.5. Oxidative Cleavage and Ozonolysis 2469 3.2.6. Metathesis 2470 4. Terpenes 2472 4.1. Pinene 2472 4.1.1. Isomerization: R-Pinene 2472 4.1.2. Epoxidation of R-Pinene 2475 4.1.3. Isomerization of R-Pinene Oxide 2477 4.1.4. Hydration of R-Pinene: R-Terpineol 2478 4.1.5. Dehydroisomerization 2479 4.2. Limonene 2480 4.2.1. Isomerization 2480...
متن کامل